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The structural diversity of highly connected metal–organic frameworks (MOFs) has long been limited due to the scarcity of highly connected metal clusters and the corresponding available topology. Herein, we deliberately chose a series of tritopic linkers with multiple substituents to construct a series of highly connected rare-earth (RE) MOFs. The steric hindrance of these substituents can be systematically tuned to generate various linker rotamers with tunable configurations and symmetries. For example, the methyl-functionalized linker (L-CH3) with C 2v symmetry exhibits larger steric hindrance, forcing two peripheral phenyl rings perpendicular to the central one. The combination of C 2v linkers and 9-connected RE6 clusters leads to the formation of a new fascinating (3,9)-c sep topology. Unlike Zr-MOFs exhibiting Zr6 clusters in various linker configurations and corresponding different structures, the adaptable RE6 clusters can undergo metal insertion and rearrange into new RE9 clusters when connected to an unfunctionalized linker (L–H) with C 1 symmetry, giving rise to a new (3,3,18)-c ytw topology. More interestingly, by judiciously combining the linkers with both small and bulky substituents through mixed-linker strategies, an RE9-based MOF with an engaging (3,3,12)-c flg topology could be obtained as a result of continuous steric hindrance control. In this case, the two mixed linkers adopt configurations with moderate steric hindrances. Molecular simulation demonstrates that the combination of substituents with various steric hindrances dictates the resulting MOF structures. This work provides insights into the discovery of unprecedented topologies through systematic and continuous steric tuning, which can further serve as a blueprint for the design and construction of highly complicated porous structures for sophisticated applications.

The separation of ethylene (C 2 H 4 )from amixture of ethane (C 2 H 6 ), ethylene (C 2 H 4 ), and acetylene (C 2 H 2 )a t normal temperature and pressure is as ignificant challenge. The sieving effect of pores is powerless due to the similar molecular size and kinetic diameter of these molecules.W e report an ew modification method based on as table ftw topological Zr-MOF platform (MOF-525). Introduction of acyclopentadiene cobalt functional group led to new ftw-type MOFs materials (UPC-612 and UPC-613), which increase the host-guest interaction and achieve efficient ethylene purification from the mixture of hydrocarbon gases.T he high performance of UPC-612 and UPC-613 for C 2 H 2 /C 2 H 4 / C 2 H 6 separation has been verified by gas sorption isotherms, density functional theory (DFT), and experimentally determined breakthrough curves.T his work provides ao ne-step separation of the ternary gas mixture and can further serve as ablueprint for the design and construction of function-oriented porous structures for such applications.

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Linker desymmetrization has been witnessed as ap owerful design strategy for the discovery of highly connected metal-organic frameworks (MOFs) with unprecedented topologies.Herein, we introduce molecular pivot-hinge installation as alinker desymmetrization strategy to evolve the topology of highly connected rare-earth (RE) MOFs,w here ap ivot group is placed in the center of al inker similar to ah inge.B yt uning the composition of pivot groups and steric hindrances of the substituents on various linker rotamers, MOFs with various topologies can be obtained. The combination of L-SO 2 with C 2v symmetry and 12-connected RE 9 clusters leads to the formation of afascinating (4,12)-c dfs new topology.Interestingly,when replacing L-SO 2 with atetrahedra linker L-O,the stackingbehaviors of RE-organic layers switch from an eclipsed mode to astaggered stacking mode,leading to the discovery of an intriguing hjz topology.A dditionally,t he combination of the RE cluster and alinker [(L-(CH 3 ) 6 )] with more bulky groups gives rise to a flu topology with an ew 8-c inorganic cluster.The diversity of these RE-MOFs was further enhanced through post-synthetic installation of linkers with various functional groups.F unctionalization of each linker with acidic and basic units in the mesoporous RE-based PCN-905-SO 2 allows for efficient cascade catalytic transformation within the functionalizedc hannels.

We present a comprehensive analysis of the submissions to the first edition of the Endoscopy Artefact Detection challenge (EAD). Using crowd-sourcing, this initiative is a step towards understanding the limitations of existing state-of-the-art computer vision methods applied to endoscopy and promoting the development of new approaches suitable for clinical translation. Endoscopy is a routine imaging technique for the detection, diagnosis and treatment of diseases in hollow-organs; the esophagus, stomach, colon, uterus and the bladder. However the nature of these organs prevent imaged tissues to be free of imaging artefacts such as bubbles, pixel saturation, organ specularity and debris, all of which pose substantial challenges for any quantitative analysis. Consequently, the potential for improved clinical outcomes through quantitative assessment of abnormal mucosal surface observed in endoscopy videos is presently not realized accurately. The EAD challenge promotes awareness of and addresses this key bottleneck problem by investigating methods that can accurately classify, localize and segment artefacts in endoscopy frames as critical prerequisite tasks. Using a diverse curated multi-institutional, multi-modality, multi-organ dataset of video frames, the accuracy and performance of 23 algorithms were objectively ranked for artefact detection and segmentation. The ability of methods to generalize to unseen datasets was also evaluated. The best performing methods (top 15%) propose deep learning strategies to reconcile variabilities in artefact appearance with respect to size, modality, occurrence and organ type. However, no single method outperformed across all tasks. Detailed analyses reveal the

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